Doing it the hard way

A project log for Twitter feed on an old LED marquee

An adventure in '80s electronics and embedded Linux

Enrico GueliEnrico Gueli 04/05/2022 at 19:261 Comment

Hacking the firmware seemed like a very complicated way to obtain a result, which could make this project very time-consuming, possibly grinding to a halt.

So I decided I wanted to give another go at the hard way, i.e. desoldering the three DIP chips that were controlling the LED driving circuitry and put my hardware in the middle.

Thanks to this Hackaday article and my hot air gun I successfully managed to desolder the MCU in its 40-pin DIP and two more logic chips.

Now it's just a matter of adding an Arduino to the right pins, to see if I can indeed control the row and column drivers.

If this is successful as well, I can replace the Arduino with a bunch of level shifters connected to the Linux embedded board.


Ken Yap wrote 04/06/2022 at 01:10 point

That's probably the way I would do it myself, one less computing element in the signal path. I'm sure you will figure out the row/column mapping.

  Are you sure? yes | no